Among acceleration sensors, shock acceleration sensors for detecting shock acceleration generated, for example, in car crash safety testing, robots, transportation equipment, equipment relating to nuclear power generation, ships, and space and aeronautical equipment and the like are widely used. When carrying out calibration and evaluation of shock acceleration sensors, conventionally, a method of installing an acceleration sensor on a mounting table of a single axis vibration table and using a laser interferometer to measure the motion of the mounting table is a technique that has been regarded as having the highest reliability and which has been used as the primary standard. However, high acceleration cannot be generated with this evaluation apparatus, and there is also the effect of parasitic rolling vibration, making inaccurate evaluations unavoidable.
When carrying out calibration and evaluation of such shock acceleration sensors, also, an apparatus is required for generating the shock acceleration. This being the case, the present inventor has previously proposed a technique in which one end surface of a metal rod is impacted with a metal projectile launched from a single launch tube, an acceleration sensor is attached to the other end surface of the metal rod, and shock acceleration arising when the internal elastic wave pulse generated by the impact of the projectile against the one end surface of the metal rod is reflected by the other end surface of the metal rod where the acceleration sensor is affixed is used to evaluate the frequency characteristics of the acceleration sensor (Japanese Patent No. 1902031, U.S. Pat. No. 5,000,030).
The above technique for evaluating shock acceleration simply impacts the metal rod with the metal projectile from a single launch tube, and therefore cannot generate narrower band shock acceleration having industrial significance, and in particular cannot control the launch timing, so has the drawbacks of the duration time of the generated shock acceleration being too short, and the frequency bandwidth becoming too wide.
Therefore, the object of the present invention is to provide an acceleration sensor calibration and evaluation method and apparatus that, in the evaluation of the dynamic characteristics of an acceleration sensor that detects shock acceleration, solves the above-described problems of the conventional evaluation technique using a vibration table and, furthermore, enables the shock acceleration waveform and frequency bandwidth to be freely controlled.